NEC PD78058FY(A) Network Card User Manual


 
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CHAPTER 17 SERIAL INTERFACE CHANNEL 0 (
µ
PD78058FY SUBSERIES)
(3) SO0 latch
This latch holds SI0/SB0/SDA0/P25 and SO0/SB1/SDA1/P26 pin levels. It can be directly controlled by
software.
(4) Serial clock counter
This counter counts the serial clocks to be output and input during transmission/reception and to check whether
8-bit data has been transmitted/received.
(5) Serial clock control circuit
This circuit controls serial clock supply to the serial I/O shift register 0 (SIO0). When the internal system clock
is used, the circuit also controls clock output to the SCK0/SCL/P27 pin.
(6) Interrupt signal generator
This circuit controls interrupt request signal generation. It generates interrupt request signals according to
the settings of interrupt timing specification register (SINT) bits 0 and 1 (WAT0, WAT1) and serial operation
mode register 0 (CSIM0) bit 5 (WUP), as shown in Table 17-3.
(7) Acknowledge output circuit and stop condition/start condition/acknowledge detector
These two circuits output and detect various control signals in the I
2
C mode.
These do not operate in the 3-wire serial I/O mode and 2-wire serial I/O mode.